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Differential Drive Lesson 3(Code)

The Code

View Differential Drive code(simulation) on GitHub

KEY SNIPPETS OF CODE

The inverse kinematics is implemented in the inverse_kinematics method of the Robot class which includes the formulas covered in the previous part of the lesson: 

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def inverse_kinematics(self, v_f, v0):
    self.vr = v_f + self.track_radius * v0  # Velocity of right wheels
    self.vl = v_f - self.track_radius * v0  # Velocity of left wheels

This involves setting each set of wheels(left and right), with the velocity calculated from the inverse kinematics. This way we are able to make our robot move. 

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def setVelocity(self): # setting velocity on the left and right wheels(you set wheels to left and right not individual in tank drive)

            for wheel in self.wheels_left:
                p.setJointMotorControl2(
                    bodyIndex=self.robot_id,
                    jointIndex=wheel,
                    controlMode=p.VELOCITY_CONTROL,
                    targetVelocity=self.vl,
                    force = 50 # i think the torque on a jackal
                )
            for wheel in self.wheels_right:
                p.setJointMotorControl2(
                    bodyIndex=self.robot_id,
                    jointIndex=wheel,
                    controlMode=p.VELOCITY_CONTROL,
                    targetVelocity=self.vr,
                    force = 50 # i think the torque on a jackal
                )